1. Field of the Invention
The present invention relates to recording apparatuses for recording according to recording data.
2. Description of the Related Art
Scanner-equipped printers that have scanner sections for taking in original images and printer sections for performing printing according to the supplied print data are known as an example of recording apparatuses that perform recording according to recording data. In scanner-equipped printers, a CPU that takes control over the entire apparatus and an external memory that is directly accessible from the CPU are connected via a bus. The RGB image data taken in from the scanner section are stored in the above-mentioned external memory via the bus, and according to processing by the CPU, the data are converted on the external memory into print data for enabling printing. The converted print data are sent out to the printer section via the bus, and the printer section performs printing according to the print data.
In conventional scanner-equipped printers as described above, the RGB image data taken in from the scanner section and the converted print data are sent out via the bus. Further, conversion from the RGB image data to the print data is a process carried out by the CPU according to software, and since data are exchanged via the bus even during this process, an extremely large amount of data flows through the bus.
The bus is also connected to the CPU that takes control over the entire apparatus, and as a matter of course, control signals also flow through this bus. That is, there has been a problem that, if the traffic in the bus is heavy, then the control process speed of the apparatus drops, and therefore, the output speed of the scanner-equipped printer becomes slow.
Further, when the CPU is handling other processes, it is necessary to wait for the bus to become free, and such controls as to forcedly interrupt the use of the bus by the CPU in order to transfer print data with higher priority become necessary.
Further, other than the function of operating as a normal printer for printing on a medium according to print data that have been sent from a host computer, the scanner-equipped printer has a function as a scanner for generating image data from an image in an original read with a scanner section and sending the data to a host computer etc. and a function as a local copier for printing on the medium the original image read by the scanner section.
The image data generated from the original image read by the scanner section are temporarily stored in a predetermined data storage area (also referred to as an image data storage area below), are successively read out from the image data storage area at appropriate timings, and are sent toward the host computer etc. Further, when the original image read by the scanner section is to be printed on a medium, the image data generated from the original image read by the scanner section are successively read out from the image data storage area and are converted into print data for printing. The converted print data are temporarily stored in a predetermined data storage area (also referred to as a print data storage area below) separate from the above-mentioned image data storage area, are successively read out from the print data storage area, and are sent to the printer section.
However, in such scanner-equipped printers, conventionally, the image data storage area for storing the image data generated by the scanner section and the print data storage area for storing the print data generated by converting the image data have been provided separately and in a fixed manner, and therefore, it has been possible to use only the image data storage area for generating the image data from the original image, and use only the print data storage area for generating the print data for printing by converting the image data. This is because the process of generating the image data from the image in the original that has been read by the scanner section and the process of generating the print data for printing from the image data are performed with separate dedicated processing circuits (ASICs), and because the image data storage area and the print data storage area are each provided respectively in a data storage section that is provided in each dedicated processing circuit.
Therefore, a so-called buffering state in which the reading operation stops right in the middle of reading an image from an original with the scanner section tends to arise. Buffering is a state that occurs when all of the image data cannot be stored in the image data storage area, and this occurs when there is a delay in a process of outputting the image data stored in the image data storage area to, for example, a host computer or a process of converting the image data into print data. Particularly, when the read resolution for reading an original is set high, the data amount of the image data that are generated becomes extremely large, and therefore, the number of times buffering occurs becomes large.
Further, as for the above-mentioned scanner-equipped printer, (1) a print mode in which the same image is repeatedly printed on one sheet of paper when small documents are to be printed on paper is known. According to this print mode, a plurality of images are arranged and printed on the paper in the vertical direction and the lateral direction. In such a print mode, the user enters the number of images to be arranged in the vertical direction and the lateral direction. Therefore, the user has to enter the number of images to be arranged in one sheet of paper after estimating how many images can be arranged on the paper.
Further, when the above-mentioned scanner-equipped printer prints an image of image data on paper, the scanner-equipped printer converts the image data into print data. The conversion from the image data into the print data is processed by a CPU of the scanner-equipped printer. If the amount of data to be processed by the CPU increases, the speed of other processes of the CPU drops, and as a result, the print speed drops. Therefore, in order to reduce the amount of data processed by the CPU, it is possible to consider providing a control circuit separate from the CPU and converting the image data into the print data with this control circuit.
On the other hand, it is necessary for the scanner-equipped printer to lay out the image of the image data for printing. Since the layout processing requires complicated computations, it is not realistic to make the above-mentioned control circuit to perform even the layout processing.
Further, when the scanner reads an image from an original, or when an application software creates an image, image data in the RGB system are generated. On the other hand, when the image data in the RGB system are printed by the above-mentioned scanner-equipped printer, the image data in the RGB system are converted into image data in the CMYK system that are matched with the colors printable by the printer section. Therefore, the scanner-equipped printer has a data conversion section for converting the image data in the RGB system into image data in the CMYK system.
There are cases in which the apparatus subjects the image of the image data to layout processing and prints the laid out image onto a medium (such as paper and OHP sheets). Therefore, the scanner-equipped printer is provided with a layout section for laying out the image of the image data based on the image data. If the amount of data processed by the layout section can be made small, the amount of time necessary for the layout process can be shortened, and therefore, it would be possible to increase the print speed of the scanner-equipped printer.